Remove `free -m` RSpec report

This doesn't provide any data which is immediately actionable. I would
suggest using `with_memory_allocations` instead if we decide to profile
RSpec memory, as it would allow us to measure the mem pressure during
the spec execution.

.gitlab/ci/rails.gitlab-ci.yml

@@ -54,7 +54,6 @@
       - knapsack/
       - rspec/
       - tmp/capybara/
-      - tmp/memory_test/
       - log/*.log
     reports:
       junit: ${JUNIT_RESULT_FILE}
@@ -571,7 +570,6 @@ rspec:coverage:
     - rspec system pg12-as-if-foss decomposed
   script:
     - run_timed_command "bundle exec scripts/merge-simplecov"
-    - run_timed_command "bundle exec scripts/gather-test-memory-data"
   coverage: '/LOC \((\d+\.\d+%)\) covered.$/'
   artifacts:
     name: coverage
@@ -580,7 +578,6 @@ rspec:coverage:
       - coverage/index.html
       - coverage/assets/
       - coverage/lcov/
-      - tmp/memory_test/
     reports:
       cobertura: coverage/coverage.xml
 

scripts/gather-test-memory-data

-#!/usr/bin/env ruby
-# frozen_string_literal: true
-
-require 'csv'
-
-def join_csv_files(output_path, input_paths)
-  return if input_paths.empty?
-
-  input_csvs = input_paths.map do |input_path|
-    CSV.read(input_path, headers: true)
-  end
-
-  CSV.open(output_path, "w", headers: input_csvs.first.headers, write_headers: true) do |output_csv|
-    input_csvs.each do |input_csv|
-      input_csv.each do |line|
-        output_csv << line
-      end
-    end
-  end
-end
-
-join_csv_files('tmp/memory_test/report.csv', Dir['tmp/memory_test/*.csv'].sort)

scripts/rspec_helpers.sh

@@ -268,10 +268,6 @@ function rspec_paralellized_job() {
 
   debug_rspec_variables
 
-  mkdir -p tmp/memory_test
-
-  export MEMORY_TEST_PATH="tmp/memory_test/${report_name}_memory.csv"
-
   if [[ -n $RSPEC_TESTS_MAPPING_ENABLED ]]; then
     tooling/bin/parallel_rspec --rspec_args "$(rspec_args "${rspec_opts}")" --filter "tmp/matching_tests.txt" || rspec_run_status=$?
   else

spec/spec_helper.rb

@@ -184,7 +184,6 @@ RSpec.configure do |config|
   config.include RedisHelpers
   config.include Rails.application.routes.url_helpers, type: :routing
   config.include PolicyHelpers, type: :policy
-  config.include MemoryUsageHelper
   config.include ExpectRequestWithStatus, type: :request
   config.include IdempotentWorkerHelper, type: :worker
   config.include RailsHelpers
@@ -244,10 +243,6 @@ RSpec.configure do |config|
     ::Ci::ApplicationRecord.set_open_transactions_baseline
   end
 
-  config.append_before do
-    Thread.current[:current_example_group] = ::RSpec.current_example.metadata[:example_group]
-  end
-
   config.append_after do
     ApplicationRecord.reset_open_transactions_baseline
     ::Ci::ApplicationRecord.reset_open_transactions_baseline

spec/support/helpers/memory_usage_helper.rb

-# frozen_string_literal: true
-
-module MemoryUsageHelper
-  extend ActiveSupport::Concern
-
-  def gather_memory_data(csv_path)
-    write_csv_entry(csv_path,
-      {
-        example_group_path: TestEnv.topmost_example_group[:location],
-        example_group_description: TestEnv.topmost_example_group[:description],
-        time: Time.current,
-        job_name: ENV['CI_JOB_NAME']
-      }.merge(get_memory_usage))
-  end
-
-  def write_csv_entry(path, entry)
-    CSV.open(path, "a", headers: entry.keys, write_headers: !File.exist?(path)) do |file|
-      file << entry.values
-    end
-  end
-
-  def get_memory_usage
-    output, status = Gitlab::Popen.popen(%w(free -m))
-    abort "`free -m` return code is #{status}: #{output}" unless status == 0
-
-    result = output.split("\n")[1].split(" ")[1..]
-    attrs = %i(m_total m_used m_free m_shared m_buffers_cache m_available).freeze
-
-    attrs.zip(result).to_h
-  end
-
-  included do |config|
-    config.after(:all) do
-      gather_memory_data(ENV['MEMORY_TEST_PATH']) if ENV['MEMORY_TEST_PATH']
-    end
-  end
-end

spec/support/helpers/test_env.rb

@@ -371,17 +371,6 @@ module TestEnv
     FileUtils.rm_rf(path)
   end
 
-  def current_example_group
-    Thread.current[:current_example_group]
-  end
-
-  # looking for a top-level `describe`
-  def topmost_example_group
-    example_group = current_example_group
-    example_group = example_group[:parent_example_group] until example_group[:parent_example_group].nil?
-    example_group
-  end
-
   def seed_db
     Gitlab::DatabaseImporters::WorkItems::BaseTypeImporter.import
   end